Keir Starmer pre-emptively challenged anyone criticising the government’s upcoming Budget to come up with their own alternatives to fix the UK.

Speaking at a press conference on Monday, the prime minister prepared the public for Labour’s first Budget in 15 years.

The Treasury has warned that it will be looking to raise £40bn in this announcement, which will unveil a series of cuts to some government departments and some tax rises in the coming months.

Labour claim this is necessary to “fix the foundations” of the country and amend the £22bn black hole it says the previous Tory government left in the UK finances.

Although the Budget is yet to be unveiled, the government has already been accused of breaching their manifesto pledge not to raise taxes on working people and of bringing back the Tories’ austerity measures.

Speaking today, Starmer snubbed those critics, saying: “If people want to criticise the path we choose, that’s their prerogative. But let them then spell out a different direction.

“If they think the state has grown too big, let them tell working people which public services they would cut.

“If they don’t see our long-term investment in infrastructure as necessary, let them explain to working people how they would grow the economy for them.

“This is an economic plan that will change the long-term trajectory on British growth for the better.

“We are tackling the biggest challenges in our economy. Higher investment – we’re dealing with it. Planning – we’re reforming it. The labour market – we’re getting people back to work, but also making work pay.

“On competition, we’re stripping out the needless regulation that holds back growth and private investment. And all of this built on that foundation, economic stability.

“This is what fixing the foundations and delivering change means. Everyone in this country will benefit from this. Everyone can wake up on Thursday and understand that a new future is being built, a better future.”

Starmer also said he expects to be “judged” by the general public on this Budget.

He said: “Because I know actions speak louder than words, because I expect to be judged by the British people.

“In the coming weeks, on every mission, we will publish clear ambitions for this parliament and we will also track our progress against them, so that every single person in this country can see exactly how we measure up to things that matter to them.

“After all, we have five years and a big mandate, so working people will not accept any excuses.”

He also hit out at the criticism around his government’s confusing definitions of the term “working people”, saying those people “know exactly who they are”.

“Every decision we will make in the future will be made with working people in our minds’ eye,” he promised.

He added: “I know some people want to have a debate about this and I know there will always be the exception that proves the rule. Welcome to the wonders of a diverse country!”